Process of making sulfur trioxid.



.No. 828,268. PATENTBD AUG. 7', 1806.

' 11. s. BLAGKMORB.

'PROGEss 0F MAKING SULFUR'TRIUXID.

APPLIOATIQH FILED DBO. 19, 1904.

2 SHEETS-SHEET l.

N0-828 .26s. v PATENTUU AUG. 7, 190e.

l U. s. BLAUKMUUU.

PRo-cUss of' MAKING SULFUR TRIUXIU.

APPLICATION FILED DEO. 19, 1904.

2 SHEETS-SHEET 2.

UETTED STATES PATENT OFFICE.

PROCESS oF MAKING SULFUR Tmoxlo.

Specicaltion of Letters Patent.

Patented Aug. 7, 1906.

Original application-filed May 11,1901, Serial No. 59,814. Divided and this application filed December 19,1904. Serial No. 237.449.

To all whom, it. may concern:

Be it known that I, HENRY SPENCER BLACKMORE, a citizen of the UnitedStates, residing at Mount Vernon, inthe county of Westchester and State of New York, have invented new and useful Improvements in Processes of Making Sulfur Trioxid, of which the following is a specification, being a division from my application, Serial N o. 59,814, filed May 11, 1901.

The object of my invention is to produce compounds containing sulfur, such as sulfur trioxid, (SOM) which evolve heatvin their formation in such a manner thatvthe temperature is prevented from rising to a point at .which the compound desired is dissociated,

whereby its continuous production is pro-- hibited; and it consists in simultaneously producing substances which absorb heat on their formation and' the sulfur compound desired, 'the ingredients being so apportioned, adjusted, and disposed that the heat evolved during the formation of the sulfur compound is abstracted by the substance absorbing heat during its production to such a degree that the L tem erature is prevented from" sulfur trioxid b a simultaneously-produced substance whic absorbs heat on its formation, the ingredients being so apportioned and disposed that the heat evolved by one is taken u by the other to such a degreeas to practica ly prevent the 'accumulation of heat to an inu'rious point. By properly apportioning the reacting ingredients the process of making sulfur trioxid may be carried on continuously, the reaction being induced by the direct application of controlled heat in preference to lheat dislodged, generated, or produced through themediation'of'catalytic or condensation action of finely-divided'metal or so called contact substances, v(61"af'rots `Phfys',cs,) such as platini'zed asbestos, &c on

gases present, which soon become inoperanections of the transforming-chamber. FigI 3 is a 'cross-section of one of the rings lof the electric connection of the transformingchamber and an electric gauze diaphragm connected therewith. Fig. 4.- is a transverse ysection of a modified form of apparatus, showing the transforming-compartments of elongated form and provided with waterjackets. Fig. 5 isa vertical longitudinal section of the apparatus on the lines Fig. 4; and Fig. 6 is a transverse vertical section o the lines y y, Fig. 4.-

Similar letters refer tocorresponding parts in the several views.

Theletter A designates a transformingy.

chamber of cylindrical or other form, provided at its top with an elbow-B andpipeO,

the latter connected a jacketed condenser D in any desired air-tight manner.

The-lower end of the transformin -chamber A is provided with a detachable ead E,I

havin a central stufIing box or screwthrea ed plug F, of insulating material, connected therewith and in which is fitted a rod or `electric connection G, the upper portion of whichI is formed in sections havingscrewthreaded connections, as shown at aa a, in Fig.) 2. The transforming-chamber A, like the electric connection G, is partly com osed of sections, as shown at b b Vb, (see Figs. 1 and 2,) the said sections being joined together by the threaded ends c c c A series of metallic-gauze diaphragms d, preferably of gold-plated copper, are arranged within the transforming-chamber A,

the said diaphragme being securely held in relative positions by the yabutting shoulders of the screw-threaded ends of the transforming-'chamber rings and, of the central connectionxthereof. The upper an'dlowerdiap s d and d are 'arranged in several thicknesses, -forming a heat-absorber and Ion' IOS

` with the electric conductor G and the walls of the tranorming-chamber A by ordinary means. Y

The lower part of the transforming-chamber is provided horizontall with a pipe-section H, having a detachab e end or head h, Within which is tightly fitted a tube l, the latter provided with a T-head l and an inletpipe m, while within the stem of the T-head and the tube-l is arran ed a pipe n for the purposes hereinafter fuly specified. A

In constructing an apparatus for carrying out my invention on a manufacturing scale it is found advisable not to have the heating gauze diaphragms d d of a width greater than two inches from the central conductor on account of the tendency of the same to sag, become overheated, and fuse. I therefore prefer the form of apparatus as shown in igs. 4;' 5', and 6, wherein it is seen that the transforming-compartments are of elongated form and the central conductor instead of a Arod consists of a strip of metal. This form of transforming apparatus is adapted to carry a heated gauze diaphra m of from three to four feet in length and our inches in widthi. e., `two inches on either side of the central conductor which extends through the center of the transforming-compartment to within two inches of either end, as shown in Fi 4. In constructin a battery of this form ofgapparati it is a visable to separate the in vidual sections from each other by means of a Water-j acket z z, which assists in maintaining the gases in a refrigerated condition, wherebyv the reaction is regulated by supply of heat thereto by means ofl heated gauze diaphra ms. In all other particulars this preferre and modified form ofapparatus is illustrated in Figs. 4, 5, and-6 in parts corresponding to Figs. 1, 2, and 3, except in form and-construction, the same letters of reference referring to corresponding parts inthe several views.

' In the operation ofmy invention for theproduction of sulfur trioxid' I introduce the sulfur dioxid through the pipe Vm and gradually introduce a gaseous oxidizing compound, such as carbon dioxid and nitrogen tetroxid, through the pipe n, allowing the y two to enter in about equivalentI proportions before reaction, Whereu on they become thoroughly mixed'in the ower art of transforming-chamber A. The mixe 'gases then pass up through the insulated gauze ilash-preventer d into the transformingcompartment A'. A current of electricity is then passed through the connections i i i, the same passing through the diaphragms d d, heating them in pro ortion to the strength of the current, either ow or to whiteness, the temperature bei'ng somewhat gaged by the color of the diaphragm, which can be observed through the mica-closed peep-holes f f. As the mixture of sulfur dioxid, carbon dioxid, and nitrogen tetroxid comes in contact with the heated gauze dia hra ms a reaction takes place which may e il ustrated by the following chemical formula or equation:

3S()2 -l-COz 2N()2 3S()3 -i- C() 2NO.

It will be observed that bthe reaction which here takes place. is of endothermic nature and the oxidizing compounds are reduced producing by-product of endothermic or eatabsorbing character-that is to say,

heat has to be supplied to the mixture to.

maintain the reaction or oxidation and can onl reach the point of dissociation of the sul ur trioxid by the excessive application of external heat. In inducing the reaction between sulfur dioxid and a gaseous oxidizing compound I heat the ignitin gauze' diaphragmsd d to a bright red y passing a current of electricity therethrough and then gradually pass the sulfur dioxid and gaseous oxidizing compound, such as carbon dioxid and nitrogen tetroxid, throu h the same. As the mixture of vsulfur dioxi carbon dioxid', and nitrogen tetroxid passes through the diaphragms d d, heated to brightredness, a reaction takes place. Thearbon dioxid and nitrogen tetroxid at that temperature assume oxidizing properties and give up a portion of their oxygen to the gaseous sulfur dioxid, producing sulfur trioxld, carbonic o'xid, and nitrogen tetroxid, which products are' rapidly conveyed from the heated sphere in juxtaposition to the dia hragm by the current of flowing gas therethrough. Care must be taken not to pass the mixture of carbon dioxid and sulfur dioxid through the diahragm at a eater speed than will cool the iaphragm vbe oWa hr1 ht red heat, as the reduction of the carbon ioxid to carbonio oxid andsimultaneous oxidation of sulfur dioxid to sulfur trioxid requiresl the addition Vof heat, for the reason that the by-pro'cluct, car- IIO bonic oxid, absorbs a large portlon of latent heat, which heat had previousl been liberlated lby oxidation to carbon ioxid. Itis well known that the oxidation oflgsulfur dioxid by means of oxygen per -se liberates heat in such quantity as to eventuallyaccw mulate to' a tem rature which prevents the formation of s r trioxid unless the sensible heat is mechanically abstracted. By my processfthe llberation of sensibleheat in assises c "V the oxidation of sulfur dioxid is entirely prevented, so that the sulfur dioxid becomes oxidized by what is termed an endothermic reaction-i. e., heat is absorbed during the reaction instead of being liberated and must naturally be supplied thereto to maintain it.

The reason for this fact is that during the an exterior source, and, in fact, the amountV of heat absorbed inreducing carbon dioxid tovcarbonic oxid in the oxidation of sulfur dioxid, producin sulfur trioxid, is so much in excess of the eat which would be liber-l ated by the direct union of sulfur dioxid withl ox en that the carbon dioxidemplo ed as 0x1 'zing agent may be mixed Wit free oxygen or nitrogen oxid, which under normal conditions produce an exothermic reaction with sulfur dioxid in such as to neutralize the heatl absorbing nature ofthe carbonic oxid as produced by the decomposition of carbon dioxid in the process. It- Will be observed that the heated sphere in juxtaposition to the dia hragm is maintained at a bright red, at Whic temper- "Y ature carbon dioxid acts as an oxidizing agent. The products passing therethrough are rapidly conveyed outside of the sphere at which heat is` supplied-fi. e., in juxtaposition to the diaphragm-so that decomposition b -by-products is thus prevented thereafter.

he pro ortion of gases in case sulfur dioxid and car on dioxid are employed is preferably in volume of two parts of carbon dioxidl to one part of sulfur dioxid, the object being to have an excess of carbon dioxid, the resence ofwhich prevents the reduction o sulfur trioxid by the carbonic-oxid byroduct as the gases cool after reaction. Ail-,ter the sulfur trioxid and carbonio oxid are thus pro- Aduced by means of endothermic reaction they are conveged through the water-jacketed condenser. Where the sulfur trioxid is condensed, and the carbonio oxid and nitric oxid, with excess of carbon dioxid, conducted tlerefrom, the carbonio oxid and nitric .oxid

oxidized by burning to carbon dioxid and nitrogen tetroxid and em loyed again, as before. The carbonic exi and'mtnc oxid 1n this process merely actas a carrier of oxygen,

`whereby the oxidation of sulfur dioxids performed4 Without-liberation of sensible heat. The reaction which would takeflace during the oxidation of .cabonic oxi roportion and nitric oxid with the evolution of heat which it had absorbed during the oxidation of sulfur dioxid yto sulfur trioxid in the process of chemical refrigeration may be illustrated by the following chemical formula or equation:

By thus employing the nitrogen oxids and carbon oxids t e process of making sulfur trioxid may be carried on continuously by employing sulfur dioxid and oxygen in separate com artments with an intermediate condenser, t e nitrogen tetroxid and carbon dioxid acting as oxidizing agents to the sulfur trioxid in the production of sulfur trioxid and the by-product, carbonio oxid, being endothermic or heat-absorbing in its formation, is dissociated in the manner described,

abstractin the heat which would normally be evolve on the oxidation of sulfur dioxid, thus preventing an accumulation of heat to a temperature at Which the formation of sulfur trioxid would be prevented. The currentof gases introduced passing rapidly through the apparatus carries the principal product of reaction-Ji. e., sulfur trioxid-quickly through and 's tvva'l from the heated gauze diaphragms,

and at t e same time lit is cooled by the surrounding body of gases and then passes through the ash-preventer d, which consists of a number of la ers of gauze insulated,

as before described, rom the central conductor, and thus also acts as a strainer or absorbent of any excess of heat absorbed from the heated diaphragms and conveys itaway, the sulfur trioxid being finally condensed m the jacketed condenser D, from which it ma be removed from time to time as desire While the carbonio oxid or other reduced oxidizing gaseous medium may be reoxidized and lern loyed in future operations. I

It ,W' be observed that the transformingcompartment A', in which the electrically- IOO heated diaphragms are located, is protected' at the inlet and outlet portionswith lheavy insulated gauze sections, which prevents the ignited mixture of gases in said compartment from conveying -the iiash or oxidizing reaction outside of the compartment *andy admits of controlling the temperature and the product by the rapidity of the admission of gases thereto during transformation. The electric diaphragms d d beingmaintained at a uniform temperature by carefully regulating the temperature of the electric diaphragms d d in conformity .with the rapidity of flow of gases introduced the production of sulfurtrioxid may be carried on continuouslyY without interru tion.

' Itis obvious that I can introduce any other 1 2 5 gaseousoxidizing agent 'with the carbon dioxid, such\ as nitrogen trioxid, free' oxygen, &c., mixed with the sulfur dioxid, the ingredientsbeing so a portioned `that-the heat evolved in the oxi ation ofithe sulfur. d ioxid IIO IIS

will be absorbed by the decomposition or reduction of the carbon dioxid to carbonio oxid in the formation of sulfur trioxid to such a dcgree as to prevent the accumulation of heat or elevation of temperature to the dissociatingoint of sulfur trioxid, at which time the oxi ation of sulfur dioxid would beprecluded, and inducing a reaction between the saine by suplying heat thereto.

t is obvious that I can introduce any other compound which will yield oxygen to oxidize sulfur dioxid to sulfur trioxid under the existing conditions, regardless of the fact that the said process of oxidation may be exothermic in its characterindependently and separately so long as I associate such exotherinic process with a compound capable of likewise oxidizing sulfur dioxid to sulfur trioxid,' with the difference that heat is absorbed or taken up by the by-product or residue of the oxidation, or, in other words, by endothermic reaction instead of exothermic, as in the first case, and provided the oxidizing ingredients of exothermic nature do not evolve heat to such excess of that absorbed by the oxidizing ingredients of endothermic nature that the vheat will accuinulate or soar upto a temperature at which the oxidation of sulfur dioxid would be precluded or at which sulfur trioxid dissociates. From this it will be seen that I can employ any exothermic method of oxidizing sulfur i dioxid to 'sulfur trioxid, such as exposing a mixture of sulfur dioxid and oxygen to a tern-A perature at which they combine, or sulfur dioxid and nitrogen oxid, or sulfur dioxid and any other oxidizing agent, provided. I asso'- ciate with such operation other oxidizing agentsthe by-products of which absorb heat to adegree which will maintain the temperatureof the reacting ingredients below the dissociating-point of sulfur'tri'oxid by chemical refrigeration, such as sup lying to the oxidizing ingredients of exot ermic nature carbon dioxid, which when imparting its oxygen to sulfur dioxid in the formation of sulfur trioxid willabsorb the heat evolved in the associated exothermic reaction, as aforesaid,

as Well as that which wouldbe evolved from the union of the oxygen displaced froml the carbon dioxid, and'forming its'equivalent of sulfur trioxid.-

It can be readily seen that the heated diaphragms d d in the transforming-compartment A serve to supply the heat whereby a reaction is induced between the sulfur dioxid and the gaseous oxidizing compound as it comes in contacttherewith, and the excessv of heat'absorbed therefrom by the passing gases or products of reaction is primarily removedthe rapid-owing gases ador absorbed b heat-absorbing diaphragm d mitted at the It is obvious that by my process .the oxida-` tion of sulfur dioxid produced by the reaction between sulfur dioxid"Y and a gaseous oxidizing compound is induced and maintained by a positive and controlled Ineanstviz., the electrically-heated gauze diaphragm through which the mixture of gases have to passand therefore is not subject to the dillcnlties found or niet with in employing catalytic or contact substances which soon become inoperative by absorption or saturation of gases and can only be reused by expensive process of separation and regeneration.

The products of reaction in the case of the employment of carbon dioxid and nitrogen tetroxid `asan oxidizing agent with sulfur dioxid are sulfur trioxid and carbonio oxid and nitric oxid, which products are conveyed through the condenser D, where the sulfur trioxid condenses and the by-product-viz., carbonio oxidl and nitric oxid-reconducted to a reservoir, from which it can be again employed from time to, time by oxidizing the saine, mixing it with more sulfur dioxid, and conveying the mixture through the appaitus andthe transforming-compartment A', whereby the process may be carried on in a continuous and uninterrupted manner.

I do not desire Vto confine myself to any particular gaseous oxidizing compound, but

ave found the nitrogen tetroxid and carbon dioxid mixture to be very efficient, the principal object being to oxidize sulfur dioxid to sulfur trioxid by the action of a gaseous oxidizing compound, the reaction of which on the. sulfur dioxid is of endotherrnie nature.

The term gaseous as employed herein with reference to oxidizing agents for transforming sulurvdioxid into sulfur trioxid is intended to include a vaporized oxidizing conipound capable of producing sulfur trioxid rom sulfur dioxid, as Well as an oxidizing gas per se. i

A s the sulurous gases irst come in contact with the gold-plated copper gauze it combines therewith, forming a coati of gold'- copper sulfid, which prevents furt er action on the metal parts and isolates the metal from further contact with the surrounding gases or fluids, but does not prevent the passage of heat therethrough for the purpose of inducing reaction. or combination between the sulfur dioxid andoxygen 'When the gauze is subjected to the action of an electric current. This coating remains, isolating the metal parts from the gases and preventing further contact therewith. 4

It can be readily seen that by employing my process for making sulfur trioxid employing chemical refrigeration sulfur ma readily oxidized from its dioxid to its trloxid condition directl and continuously, for -the' fur is thus abstracted and prevented from accumulating to apoint at which the .sulfur peroxidation would be precluded.

bev

IIO

Having now described my invention, what `I claim as` new, and desire to secure by Letwhile subjecting the reacting ingredients to ychemical refrigeration of another reaction.

2. The process, which consists in oxidizing a substance which upon oxidation will form sulfur trioxid while subjecting the reacting ingredients'to chemical refrigeration of another reaction.

3. The process, which consists in oxidizing a substance which, upon oxidation., will form a sulfur and oxygen containing compound,

vby the action of an oxygen-yielding substance while subjecting the reacting ingredients to Achemical refrigeration of another reaction.

'4. The process, which consists in oxidizing a substance which, upon oxidation, will form a sulfur and oxygen containin compound, by the action of oxygen of a su stance containing oxygen while subjecting the reacting. 2S

mgredlents. to chemical refrigeration of anot er reactlon. 1

5. The process, which consists in oxidizing a substance which, upon oxidation, Will form a sulfur and oxygen containing compound, by the action of an oxid of nitrogen While subjecting the reacting ingredients to chemical refrigeration of`another reaction.

, 6. The-process, which consists in oxidizing ai substance which, upon oxidation, will form sulfur trioxid, by the \ac`tion of an oxygenyielding substance while subjecting the reacting ingredients to chemical vrefrigeration of another reaction. Y

7, The process, Whichconsists in oxidizing a substance which,' upon oxidation, Will form sulfur trioxid, by the action 'of oxygen of a substance containing oxygen while subjecting the reacting ingredients to chemical refrigeration of another reaction.

8. The process of making sulfur trioxid, which consists in oxidizing sulfur .dioxid by the action of an oxid of nitrogen While subjecting the reacting ingredients to chemical refrige'ration of another reaction.

9. The process, which consists in oxidizing a substance which, upon oxidation, Will form sulfur trioxid, by the combined action of an oxid of nitrogen and a gaseous oxidizing agent capable of yielding a heat-absorbing by-product, and so proportioning and disposing the oxidizing ingredients that the forniation of sulfur trioxid will continue and be maintained at a temperature'below itsdissociatingoint, by chemical refrigeration.

c10.- -he process of making sulfur trioxid, which conslsts in oxidizing sulfur dioxid by the combined action of an oxid of nitrogen and carbon dioxid, and so pro ortioning and disposing the oxidizing ingre ients that the formation of sulfur trioxid Will continue and be maintained at a temperature below its dissociatingl-point, by chemical refrigeration.

1,1. T e process of making sulfur trioxid, which consists in oxidizing sulfur dioxid by the action of anoxid of nitro en While associated with ingredients capable of producing an inde endent and inert substance With the absorption of heat.

12. The process,which consists in oxidizing a substance which, upon oxidation, will form sulfur trioxid, by the action of an oxid of nitrogen in the presence of a substance ca able of being dissociated by the action of an With the absorption of heat.

13. The process of making sulfur trioxid, which consists in oxidizing sulfur dioxid by the action of an oxidf'of nitrogen inthe resence of a substance capable of -being issociated by the action of and with the absorption of heat.

14.v The process,which consists in oxidizing a substance which, uponoxidation, vgill form sulfur trioxid, by the action of nitrogen tetroxid in the presence of a substance ca able of being dissociated by the action of an With lthe absorption of heat.

15. The process of making sulfur trioxid, which consists inoxidizing sulfur dioxid by the action of nitrogen tetroxid in the resence ofa substance capable of being issociated by the action of and with the absorption of heat.

16. The process, which consists in oxidizing a substance which, upon oxidation, will form sulfur trioxid, by the action of an oxid of nitrogen and simultaneously producing a substance capable of absorbing heat during its formation, and ap ortioning and disposing the in edients so t at the heat which would resu t by the oxidation of the sulfur b action of the nitrogen oxid, is absorbed by t e other to such a de ee that the generation of a tem- 'below the dissociating-point of sulfur trioxid.

18. The process, which consists in controlling the evolution of sensible heat While `oxi dizin asubstance which, u on oxidation, Will orm sulfur trioxid, by t e action-of an oxid of nitro en, by removing the heat evolved from t e sphere of formation ofthe sulfur trioxid by associating therewith substances capable of chemically absorbing heat during reaction,- separating the compound IIO.

containing the chemically-absorbed energy from the sulfur trioxid, dischar ing the energy therefrom thereafter by c emical action,. and producing a substance capable of` being reused as a chemical refrigerant in the further continuance of the process.

n 19. The process, which consists in oxidizing a substance which, upon oxidation, will forni sulfur trioxid, by the action of an oxid of nitrogen and carbon dioxid.

20. The process of making sulfur trioxid, which consists in oxidizing sulfur dioxid by the action 'of an oxid of nitrogen and carbon dioxid.. f

21; The process, which consists in oxidizing a substance which, umm oxidation, will form trogen tetroxid and carbon dioxid.

22. The process of making sulfur trioxid, which consists in oxidizing sulfur dioxid by the combined action of nitrogen tetroxid and carbon dioxid.

23. The process, which consistsin oxidizing a substance which, upon oxidation, will form sulfur trioxid, while supplying carbon dioxid thereto.

In witness whereof I aiix my signature in presence of two witnesses.

HENRY .SPENCER BLACKMORE.

Wltnesses: l

H. N. JENKINS, C. C. WRIGHT.

. sulfur trioxid, by the combined action of nii 

